[Wbo2] Using the Bosch WB sensor with L1H1 circuit board

[Ron Vinsant]

All, I just checked the Motec site and looked at their Lambda meter.. 
They claim a +/- 1.5% accuracy (depending on sensor, NTK or Bosch, the 
Bosch uses a PID control for the heater and is more accurate over input 
voltage variations than the NTK)
It would seem that the calibration is based on the sensor and the 
accuracy based on the control of the heater. I will try to find out how 
the calibration is accomplished.

Ron


bcroe at juno.com wrote:

>I should have said this was in respect to the NTK sensor.  
>I don't have practical experience with the Bosch, though 
>it probably is not a quantum leap ahead.    
>
>I don't know of any release of a calibration circuit for the 
>NTK sensor.  But there were some equations leaked out.  
>A circuit can be built to exactly follow an equation, even 
>if it is different from the mfgs circuit.  That was done 
>on the first DIY-WB, and the results seem to be pretty 
>good.  But we don't officially have that equation.  As I 
>have said, trying to squeeze another decimal place of 
>absolute accuracy out of the ckt is a waste for engine 
>tuners.  Much more important was wide dynamic range 
>in the DIY-WB unit, for which fixes have been described.  
>
>There was thought that an official NTK wide band unit 
>might be available for testing.  This would allow determining 
>the equation exactly, without even opening the unit.  Can you 
>say, "reverse engineer"?  But this was never actually done.  
>
>Bruce (experienced reverse engineer) Roe
>
>23 Nov 2005 Peter Gargano <peter at techedge.com.au> writes:
>  
>
>>bcroe at juno.com wrote:
>>    
>>
>>>>when an OEM WBO2 sensor is replaced is the ECU recalibrated?
>>>>        
>>>>
>>>How would it be recalibrated?  The ECU accepts the accuracy the 
>>>calibration resistor provides, which is good enough.  Bruce Roe
>>>      
>>>
>>All the Bosch LSU sensors I've seen are laser trimmed. The Bosch 
>>specifications for the sensor make it very clear how the sensor 
>>calibration component is used to account for variation between 
>>sensors, so it's not rocket science to create a circuit that will 
>>work pretty well with the complete range of sensors that may 
>>be plugged in.
>>
>>On the other hand, the problem with the NTK sensors is that 
>>Honda/NTK never (to the best of my knowledge) made the 
>>calibration component's use public, and the cal part of DIY-WB 
>>circuit was a reverse 
>>engineering exercise with a bit of guess work.
>>    
>>
>_______________________________________________
>Wbo2 mailing list
>Wbo2 at diy-efi.org
>http://lists.diy-efi.org/mailman/listinfo/wbo2
>
>
>  
>